A conventional suspension system for a vehicle is equipped with a so-called hydraulic shock absorber by which is generated a damping force with respect to a motion of the wheel and the vehicle body toward and away from each other. Because such a motion can be considered to be a stroke motion of the wheel relative to the vehicle body, the motion will be hereinafter referred to as “stroke motion” where appropriate. Recently, in place of such a hydraulic damping-force generating device, there has been proposed a suspension system equipped with a damping-force generating device as disclosed in the following Patent Document, namely, a device configured to generate a damping force that depends on a generation force generated by an electromagnetic motor. Such a suspension system is a so-called electromagnetic suspension system (hereinafter abbreviated as “electromagnetic suspension” where appropriate). The electromagnetic suspension is configured to appropriately control the magnitude of the damping force by controlling the generation force of the electromagnetic motor. That is, the electromagnetic suspension is installed on the vehicle while utilizing good controllability of the electromagnetic suspension, thereby improving the ride comfort of the vehicle, the steering stability, and so on.
[Patent Document 1] JP-A-8-197931